Register scopes automatically for PRM

Author: patrickkang

examples/example-fastmcp-mcp/src/auth0/authz.py

@@ -5,8 +5,11 @@
 
 from mcp.server.fastmcp import Context
 
+from . import Auth0Mcp
 from .errors import AuthenticationRequired, InsufficientScope
 
+# Collect required scopes from all decorated functions
+_scopes_required: set[str] = set()
 
 def require_scopes(required_scopes: Iterable[str]):
     """
@@ -19,6 +22,10 @@ async def my_tool(name: str, ctx: Context) -> str:
         return f"Hello {name}!"
     """
     required_scopes_list = list(required_scopes)
+
+    # Collect scopes when decorator is applied
+    _scopes_required.update(required_scopes_list)
+
     def decorator(func):
         @wraps(func)
         async def wrapper(*args, **kwargs):
@@ -39,3 +46,9 @@ async def wrapper(*args, **kwargs):
             return await func(*args, **kwargs)
         return wrapper
     return decorator
+
+def register_required_scopes(auth0_mcp: Auth0Mcp) -> None:
+    """Register all scopes that were collected from @require_scopes decorators."""
+    if _scopes_required:
+        auth0_mcp.register_scopes(list(_scopes_required))
+        _scopes_required.clear()

examples/example-fastmcp-mcp/src/tools.py

@@ -3,16 +3,14 @@
 from mcp.server.fastmcp import Context
 
 from .auth0 import Auth0Mcp
-from .auth0.authz import require_scopes
+from .auth0.authz import register_required_scopes, require_scopes
 
 
 def register_tools(auth0_mcp: Auth0Mcp) -> None:
     """
     Register all tools with the MCP server.
     """
     mcp = auth0_mcp.mcp
-    # Register scopes used by tools for Protected Resource Metadata
-    auth0_mcp.register_scopes(["tool:greet", "tool:whoami"])
 
     # Tool without required scopes
     @mcp.tool()
@@ -50,3 +48,6 @@ async def whoami(ctx: Context) -> str:
             "scopes": auth_info.get("scopes", []),
         }
         return json.dumps(response_data, indent=2)
+
+    # Register all scopes used by tools for Protected Resource Metadata
+    register_required_scopes(auth0_mcp)